Postgres failing to start

[chbrandt]

Trying to start, postgres raises the following message

* Starting PostgreSQL 9.4 database server                                                                                                                               * Removed stale pid file.
The PostgreSQL server failed to start. Please check the log output:
2015-10-22 15:35:57 UTC [32-1] FATAL:  could not access private key file "/etc/ssl/private/ssl-cert-snakeoil.key": Permission denied

Of course, the server does not start and everything else fails.

[chbrandt]

This is a well discussed issue around docker/aufs containers where confusion on how aufs treats files modified in different layers appear on permissions.
For the main discussion about it, see:

• unexpected file permission error in container moby/moby#783

For other lateral/example discussions, see:

• FATAL: could not access private key file "/etc/ssl/private/ssl-cert-snakeoil.key": Permission denied sous-chefs/postgresql#156
• UTC FATAL: could not access private key file "/etc/ssl/private/ssl-cert-snakeoil.key": Permission denied puntonim/docker-postgresql93#2

[chbrandt]

Since it is a problem touching file permissions, one can try to manual fix the problem, like in this comment. Or something like that, people have been discussing.

The better solution, though, is to use DeviceMapper as the fs driver, instead of AUFS. At least that is what people there (at docker and surroundings) are proposing. So, to change your storage driver, add the option --storage-driver=devicemapper to your daemon initialization options. See this blog for a direct recipe on it, and the official documentation for completeness.

[chbrandt]

Just keep it open as a source of info before I put it clear in ("known issue") documentation. (when there is a documentation actually :-P)

[chbrandt]

I tried to use '--no-cache' when building the image (like suggested by this comment) and it looks like it worked.
If it works, I have to understand how to force it when autobuilding.